Radiator for automobiles and the like



F. IVI. OPITZ.

RADIATOR FOR AUTOMOBILES AND THE LIKE.

APPLICATION FILED IIOV. 5, I9I7.

.Pafn Mam. E5, IOZIL.

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FRED -M. OPITZ, OF RACINE, WISCONSIN, .ASSIGNOR, BY DIRECT AND MESNE ASSIGN- MENTS, TO PERFEX RADIATOR COMPANY, OF RACINE, WISCONSIN, A CORPORATION 0F WISCONSIN.

RADIATOR FOR AUTOMOBILES AND THE LIKE.

Specification of Letters Patent.

Patented Mar. i5, 1921.

Application led November 5, 1917. Serial No. 200,252.

T o all ill/tom it may concern:

Be it known that I, FRED M. OPrrz, a citizen of the United States, residing at Racine, in the county of Racine and State of Wisconsin, have invented a certain new and useful Improvement in Radiators for Automobiles and the like, of which the followin is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to radiators for automobiles and 'the like. v

Radiators of the automobile-type are subject to very severe requirements, both as to eilciency, structural economy and reliability. Inthe case of radiators of the stationary type, no particular limit is generally imposed upon size or weight and consequently eiiciency may be secured at the expense of structural economy; but in the automobiletype, the radiator must be strictly limited in size, light in weight, highly efficient in operation, and Adependable in operation. Such a radiator is required to work under variable and even adverse conditions of draft, temperature and load, with little or no attention. It must be completely watertight because of the small water contents and the seriousness of the loss of any of the same. y Y

It must be suiciently strong from a structural standpoint to withstand the lhard. usage to which it is subjected. Another prime requirement is a pleasing appearance and particularly a cellular structure or appearance is highly desirable.

A further factor is the lmatter of cost. To meet competition successfully on the market,`the cost of the radiator must be relatively low.

Numerous forms or automobile radiators have been developed to meet these requirements. Many of them are satisfactory in one or more respects.

It is an object or my invention to provide a radiator which can be manufactured yat low cost and which canmeet the requirements oi' thermal elhciency, structural economy, reliability and satisfactory appearance.

I secure these objects by forming a radiator having vertical tubes with odset lateral grooves or channels (preferably semi-circular). The tubes are placed side by side in Contact so that a solid core results with the lateral channels of the tubes registering to form air passageways from front to back. I have found that markedly improved results are obtained by the use of the substantially cylindrical -air passages thus formed. Passages of this shape allord a maximum radiating surface andpermit a maximum flow of air through the radiator. The passages need not be strictly circular in cross section however since similar results may be obtained by the use of passages whose cross sections are oval, octagonal, decagonal, etc. Each tube may be formed from a pair of strips of metal forming the opposite sides thereof or each may be formedlfrom a single strip of meta-l of twice the width of the tube, plus folding and sealing margins.

In the latter instance the strip is rolled or stamped to form two rows vof lateral corrugations in staggered relation, with a folding margin between and sealing margins on the outside of the row. The corrugated blank is then folded on the folding margin, between corrugations, to bring the sealing margins together. These margins are then overlapped to form a tight joint., which may be sealed further with solder.

The tubes thus formed are set against each other with the channels ot one tube in register with the channels ,of the adjacent tube and withthe projecting portions between channels soldered together.

ln closing ed' the top of the tubes, the walls of adjacent tubes are pressed together and soldered so that practically the entire top of the core is open, A binding strip is then placed on the front andcback edge of top and bottom and these binding strips close od the edges of top and bottom. Upper and lower headers may then be attached in any preferred manner and any suitable casing applied.

ln order to apprise those skilled in the art how to construct and utilize my invention, l shall now describe a particular embodiment oil the invention which ll have constructed.

the accompanying drawings, which form a part ci the present specification,

'Figure l is a plan View or the outer surface of the blank, having lthe indentations formed therein, in accordance with my invention.

Fig. 2 is an end elevation ci the blank folded together into the form of a tube.

Fig. 3 is a front elevation of a fragment of the upper end of the core.

Fig. 4 is a fragmentary isometric view of the upper part of the core, just previous to applying the binding strip shownin Figs. 5 and 6.

Fig. 5 is a plan view of the binding strip before folding.

Fig. 6 is an end view of the binding strip and illustrating the manner of folding the same.

In construction the blank shown in Fig. 1, l use a strip of thin copper or alloy, the width of which is twice the width of the tubes plus folding and sealing margins. The sheet is then stamped or rolled into the form shown in Fig. 1, with two rows of indentations, 1 an'd- 2, having the folding margin 3 between them and having the sealing margins lr-5, which are adapted to be joined together, to seal the ends of the tube.

The indentations are formed in the shape of unsymmetrical corrugations, to leave a semi-circular groove or channel 6 between the flattened parts 7, which are really the bottoms of the indentations. The ends 7 of the indentations are preferably, though not necessarily, formed iiat and substantially at right angles to the plane of the sheet so that when the several tubes are assembledl to form a radiator, these ends form substantially flat front and rear walls. The bottoms vof the joining channels 6 may be other than round, as, for instance, hexagon, square or Octagon. rlhese semi-circular grooves 6 are slightly flared at the ends as shown at 8. It will be noted that the corrugations of the row 1 are offset half the pitch distance with respect to the corrugatiohs of the row 2.

The margin portions are held substantially Hat between the dies during the drawing of the indentations and by means of the transverse tension produced in the sheet andv the holding of the .sheet against buckling between the dies, l am enabled to compress the margins longitudinally and thus thicken and strengthen them. 7While these marginsI are not absolutely flat as they leave the dies, they are substantially so without any deep transverse wrinkles or grooves. rlhe surplus len h in the margins is thus made of benefit in thickening, strengthening and stiffening the margins, making it possible to use very light gage sheet metal in the production of vthe tubes, and they withstand the strain, incident to the folding lstep for completing the tube, without rupturing or cracking.

r1`he blank shown in Fig. `1 is folded over from the dotted line position shown in Fig. 2 to the full line position shown in said figure, along the line A-B at the middle of the folding margin 3. 1t will be noted that strong and is the sealing margin 5 is slightly wider than the margin 4, so that sufficient metal is provided for forming an overlap as is shown at 10 in Fig. 2. 1t will be noted that the flared portions 8 are substantially tangent with the margins 3, 4 and 5 so that when these margins are folded together the flared portions will make it appear' that the depressed part is so deep as to extend flush or tangent with the sealing and folding margins. This leaves a clear passageway 1l through the tube from end to end. The projections 7 form laterally offset pockets from the main bore of the tube 11, giving a large superficial cooling area and a large ratio of cooling surface to'water contents.

After the tubes have been closed by folding as shown at 10, the tubes are placed side by side, so that the projections 7 register with each other on adjacent tubes, forming the round openings 12 and in this position the tubes have their faces dipped in solder to hold the tubes together in a solid core and to seal the individual joints 10. The cylindrical openings 12 are formed by the registering semi-circular depressions 6 on the sides of the tube.

The ends of the tubes are finished off as follows The adjacent walls which form the projections 7 are soldered together as shown at 13. `Where the depressions 6 face each other, the walls thereof are'crushed t0- gether as shown at 14, thus leaving they entire top of the core Substantially open. A binding strip 15 is stamped out as shown in Fig. 5 with ears 17 and 18 on one edge. rlhe convexears 17 are adapted to fit into the rounded openings 16 formed at the top of the core between adjacent depressed portions 6. The concave 'ears 18 fit over the outer walls of the tubes 12 which are adjacent to the top of the core.

rThis strip is folded along the central line E--F and the lugs 17 -18 are bent down to the lposition shown in Fig. 6. r1`he front edge 15 projects out, flush with the edges of the ribs 19 formed by the folding and sealing margins on the edges of the tubes. Such strips are attached at front and rear, onl top and bottom. The strip is fastened in place by solder when the faces of the core are dipped.

The core being thus built up is then provided with an upper and a lower header, as is well'understood by those skilled in the art, and is then mounted in a suitable casing to conform to the design of the a paratus with which it lis to be employed. s this is well understood by those skilled in the art, no specific instructions arenecessary.

The resulting structure isl mechanically completely water-tight. Due to the solidity of the structure, the sheet metal from which the tubes are constructed may be of light gage, thus securing quick and efiicientheat transfer. The tubes have ample opening 11 through them so that there is no danger of cloggin I do not intend to be limited to the precise details of construction shown or described and do not intend to be limited strictlyA to the manner of procedure above outlined.

I claim:

1. In a radiator core a plurality of contiuous upright tubes of sheet metal each tu e being substantially rectangular in cross section, the front walls of the tube and the rear Walls of the tube having continuous central joining margins running longitudinally only of the tube, the side Walls being indented With semicylindric'al indentations and adjacent tubes being matched to bring coperative indentations into register to form vsubstantially cylindrical air passages the indentations on one side of each tube being offset bv half the pitch distance with repect to the indentatlons on the other s1 e.

2. In combination a pluralityof contiguous upright tubes formed of sheet metal each tube bein substantially rectangular in cross section troughout and being formed of a single sheet folded centrally and having its edges folded together in a single straight line, to form a c osed tube at front and rear each side of the tube having substantially semic lindrical indentations, said indentatlons o contiguous tubes being brought into register to form completely Water surrounded air cells whereby the water tubes and air cells are completed with a finished front and back before the application of any sealin material.

In witness whereo I hereunto subscribe my name'this 30 day of October, A. D. 1917.

FRED M. OPITZ. 

